-99.4% is the change from 504 to 3
Calculation steps:
[( 3 - 504 ) ÷ 504] x 100 = -99.4%
Formula
Percentage change = [(3 - 504) / 504] x 100
Subtract the new number by the original number
3 - 504 = -501
-501 ÷ 504 = -0.9940476190476191
-0.9940476190476191 x 100 = -99.4%